Marine propulsion motors



Feb. 17, 1970 s. DAVIS 3,495,407

, MARINE PROPULSION morons Filed April 16,- 1968 i mu u Vllllllllllllllll INVENTOR. SYOIV Y 04 7/5 ATTOR/VE United States PatentUS. Cl. 60-222 2 Claims ABSTRACT OF THE DISCLOSURE This disclosurerelates to marine propulsion motors, and particularly to marinepropulsion motors of the type in which the propulsion is provided by thereactive force of jets of water projected from the marine vessel.

A marine propulsion motor according to the present This inventionrelates to marine propulsion motors, and particularly to marinepropulsion motors of the type in which the propulsion is provided by thereactive force of jets of water projected from the marine vessel.

Heretofore, marine jet propulsion motors have included an impeller meansadapted to direct water radially to a nozzle to project a radial jetstream from the nozzle. The jet streams of water projected radially fromthe nozzle were redirected by conduit means so that the jet streamscould be projected axially from the stern of the vessel. The conduitmeans utilized for redirecting the radially flowing jet streamsdispersed the jet streams thereby causing random fluctuation in thewater velocity of the jet streams. The random fluctuations causedturbulence in the jet streams, thereby reducing the maximum energyavailable from the motor as well as the efficiency of the motor.

It is an object of the present invention to provide a marine propulsionmotor wherein the jet streams are projected axially from the nozzles.

Another object of the present invention is to provide a marinepropulsion motor capable of projecting jet streams without substantialturbulence.

Another object of the invention is to provide a hydraulic jet propulsionmeans so arranged as to reduce ducting to a minimum thereby reducingweight of metal and weight of water contained in the propulsion meansand providing a more compact apparatus easier to fabricate and installthan heretofore realized.

Another object of the present invention is to provide a hydraulic jetpropulsion motor having means for selectively increasing and decreasingthe thrust of the motor.

A marine propulsion motor according to the present invention includesimpeller means arranged in a housing to direct water toward a statormeans, the stator means being so arranged and disposed within thehousing as to redirect the water axially toward a nozzle means, and thejets of water emitted from the nozzle means are projected axially.

According to an optional and desirable feature of the present invention,the stator means includes means for selectively increasing anddecreasing the thrust of the motor.

The above and other features of this invention will be more fullyunderstood from the following detailed description and the accompanyingdrawings, in which:

FIG. 1 is a side view, partly in cutaway cross-section of a marine jetpropulsion motor according to the presently preferred embodiment of theinvention;

FIG. 2 is a view taken at line 2-2 in FIG. 1;

FIG. 3 is a perspective view of a stator means for use in the motorillustrated in FIG. 1;

FIG. 4 is a partly cutaway end view of the motor illustrated in FIG. 1having impeller and stator means schematically shown to illustrate theprinciple of operation of the motor;

FIG. 5 is an end view of a modification of the motor illustrated in FIG.1; and

FIG. 6 is an enlarged section view as in FIG. 1 of a portion of themotor illustrated in FIG. 1 showing a portion of the stator means shownin FIG. 3 taken at line 66 in FIG. 3.

In the drawings, there is illustrated a marine propulsion motoraccording to the present invention. The motor is preferably locatedabove the surface level of the Water, and a suction or intake pipe 10opens into the bottom of the boat and curves upwardly and then axiallyand is connected to inner casing member 11 of a centrifugal pump 12.Drive shaft 13 of pump 12 extends into the intake pipe 10 through abearing 14 and is fitted with a packing gland 15. Inner casing member 11is secured to the transom of the boat (not shown).

Pump 12 comprises a blade hub 16 keyed to shaft 13 by key 16a. Aplurality of pump blades 17 forming an impeller or rotor of appropriateconfiguration is mounted on the blade hub 16. Pump casing 11 tapers incrosssection from its intake end 18 toward its outer periphery 19.Blades 17 extend from the hub 16 and part Way to the outer periphery ofthe casing 11. The blades are preferably wider at the hub ends than attheir outer ends so as to closely fit within casing 11.

The outer face of the pump casing is closed by a back plate 27peripherally mounted to casing 11. Plate 27 may be secured to casing 11in any suitable manner, such as by means of threaded fasteners (notshown) or the like. Plate 27 includes a central hub portion 28 providedwith an outboard bearing 29 adapted to receive portion 30 of drive shaft13. Plate 27 is also provided with a plurality of peripheral axialnozzles 31.

A plurality of fixed stator blades 20 is positioned to occupy the outerportion of the periphery of the pump casing and may be mounted thereinin any suitable manner. By way of example, body portion 20a of statorblades 20 may be cast together with back plate 27 or may be weldedthereto. The tip portion 21 of each stator blade 20 is pivotally mountedto the fixed portion 20a of the stator blade by means of pin 22. Eachpin 22 is fixedly mounted to a lever 23 which in turn is fixedly mountedto a pin 24. Pins 24 register with slots 25 in ring 26. The slots are soarranged that as ring 26 is rotated about its axis, each lever 23 isrotated to rotate all pins 22 in unison.

Rotation of pins 22, causes pivoting of the corresponding tip portion 21of the stator blades.

As shown particularly in FIGS. 3 and 6, the body portions of statorblades 20 are of such configuration as to direct water in an axialdirection. The body portions 20a of the stator blades terminate adjacentapertures 33 which lead to nozzles 31. The body portions 20a of statorblades 20 include flow-diverting surfaces 40 and 42 which cooperate withflow-diverting surface 44 on plate 27 and flow-diverting surface 46 onhousing 11 to divert flow of water axially toward apertures 33 andnozzles 31. Particularly, surfaces 44 and 46 are so arranged anddisposed as to redirect water axially toward the nozzles. For thisreason, surfaces 44 and 46 are disposed substantially radially adjacenttips 21 of the stator blades and are to an axial disposition adjacentthe nozzle openings. Preferably, the fluid-diverting surfaces on thestator blades are disposed tangentially so that water directed from theimpeller flows without substantial turbulence toward the nozzles. Theflow-diverting surfaces on the stator blades are disposed betweensurfaces 44 and 46 to direct the water to the nozzles.

In the operation of the marine motor according to the present invention,shaft 13 is driven by a suitable engine (not shown) thereby rotatingimpeller or rotor blades 17. The rotor blades direct water radiallytoward the stator blades. The stator blades redirect the water axiallytowardthe nozzles. The tips of the stator blades are connected via hingepins 22 to ring 26 so that the lead of the stator blades may beselectively altered. The tips of the stator blades may be advanced toobtain greater thrust during periods of acceleration and may be retardedfor high efliciency during periods of steady cruising.

In FIG. there is illustrated a modification of the nozzle arrangementaccording to the present invention. In the embodiment illustrated inFIG. 5, the water is emitted through openings 34 which are in the formof a peripheral ring of slots. Water directed by the stator bladesthrough apertures 33 is emitted through slots 34 in plate 35 in the formof a thin sheet of high speed water.

With a marine propulsion engine according to the invention, the waterjets are directed axially from the engine. The stator blades redirectwater to flow axially, thereby substantially reducing loss of energy andturbulence. With a marine engine according to the present invention,velocities of up to 45 knots have been realized.

The engine according to the present invention is simple in constructionand capable of operating at relatively high efficiency. The selectivepositioning of the stator blade tips permits advancement of the statorblades to obtain high thrust and retarding of the stator blades toobtain high efficiency of the motor.

This invention is not to be limited by the embodiment shown in thedrawings or described in the description, which is given by way ofexample and not of limitation.

What is claimed is:

1. Propulsion means for a vessel comprising:

an intake for fluid through which the vessel is propelled;

a shaft adapted to be rotated about an axis;

an impeller mounted on said shaft and adapted to receive fluid from saidintake;

a stator adapted to receive fluid from said impeller in a directionperpendicular to the axis of said shaft and having I arcuate bodyportions fixed with regard to said impeller and tip proportionspivotable with regard to said body portions;

control means connected to said tip portions of said stator arranged topivot said tip portions and nozzle means adapted to receive fluid fromsaid body portions of said stator in a direction parallel to the axis ofsaid shaft and to eject fluid from the vessel in jet form.

2. The propulsion means of claim 1 wherein said control means includeslever means connected to all said tip portions of said stator arrangedso that all tip portions are pivoted simultaneously and to the sameextent.

References Cited UNITED STATES PATENTS 1,042,506 10/1912 Vallat 115-163,174,454 3/1965 Kenefick -221 XR 3,237,563 3/1966 Hartland 103-97 XR3,283,737 11/1966 Gongwer 60-222 XR FOREIGN PATENTS 13,502 4/1911France. 22,381 10/ 1906 Great Britain. "1,020,3 83 2/ 1966 GreatBritain.

MARK M. NEWMAN, Primary Examiner r A. D. HERRMANN, Assistant ExaminerUS. Cl. X.R. 103-97; -16

